This invention relates generally to a bleed back control assembly for controlling blood loss during vascular diagnostic or interventional procedures, such as insertion and removal of catheters from a patient's blood vessels.
Treatment of patients with diseases, such as coronary heart disease, can typically involve use of catheters, balloon catheters, stents, and other vascular intervention devices which are introduced transluminally, i.e. to and through the interior of a patient's blood vessels. Typically, catheterization procedures include the use of a hemostatic valve to reduce blood loss.
It is known in the art to provide a large bore rotating hemostasis valve (RHV) which attaches to the end of a guiding catheter and acts as an open/close valve. After a device is introduced into the lumen of an RHV, the RHV serves as a seal around the device to reduce blood loss. An RHV must be opened to allow introduction of an interventional device into the RHV's lumen, and must be closed to control blood loss while allowing device adjustment, such as moving it back and forth. A doctor must adjust a screw cap of a conventional RHV in order to adjust the seal around various devices introduced axially through the RHV's lumen. Conventional RHV's utilize a Touhy-Bourst seal design, which may be opened and closed by the user, but such a seal allows fluid to escape until properly adjusted.
A significant amount of the patient's blood may be lost during these adjustments of the RHV's screw cap which are required in order to move a device, such as a catheter, in and out of the RHV. When the RHV is not adjusted to seal around the device introduced in the RHV's lumen, there is no mechanism for inhibiting substantial bleed back or blood loss.
Accordingly, a conventional RHV allows excessive blood loss when the RHV is not adjusted or whenever the RHV is in the open position. This drawback in an RHV allows for excessive and undesirable blood loss from the patient. The excessive blood loss also creates a more ensanguined operating environment for the user of the RHV, increasing risks associated with unwanted exposure to blood (or other fluids) and making more difficult the manipulation or operation of devices.
For example, U.S. Pat. No. 5,269,764, issued to Vetter et al., discloses a hemostatic gasket and valve assembly, including a terminal plug, which can be rotated and thus tightened to cause radial compression of the hemostatic gasket.